WhatsApp Business Calling API: A Practical Guide

Many customers would rather tap the call button in a WhatsApp chat than dial a phone number. With the WhatsApp Business Calling API, those calls can ring in a browser, reach the right person on your team, and sit in the same thread as the chat. You can also call customers back, once they allow it.

Two kinds of calls

What you need

• A number fully on the Cloud API. Numbers using coexistence keep their calls in the WhatsApp Business app.
• A messaging limit of at least 2,000 customers a day. Our Business API setup guide explains how the limit rises.
• Calling switched on in the number's call settings.
• A payment method on the account, if you plan to make calls.

Calling a customer: the permission rules

You can't call a customer out of the blue. First you ask, either with a message inside the 24-hour window or with a template outside it. These requests are charged like any other message.

• You can ask at most once in 24 hours and twice in 7 days.
• A customer can allow calls for 7 days or permanently, and can take permission back at any time.
• After 2 unanswered calls in a row, WhatsApp asks the customer whether they still want your calls. After 4, permission is removed automatically.
• Any connected call resets the request limits.

The practical rule: ask when the customer has a reason to say yes, such as "Can our engineer call you to fix the installation date?", and call when you said you would.

What it costs

• Calls customers make to you are free.
• Calls you make are billed in 6-second pulses at the rate for the customer's country, and part of a pulse counts as a whole one. A 56-second call is billed as 10 pulses.
• Rates fall as your monthly call minutes grow.
• Call recording and transcription are free for now. Meta has said they will be priced separately later.

Settings worth knowing

• Business hours: outside them, customers can ask for a callback instead of calling.
• Call button visibility: show or hide the call icon, or show it only to customers in certain countries.
• Call buttons in messages: templates can include a call button, with an expiry, and tag where each call came from.

What we learned building it

We added calling to Querygen in October 2026, and these five problems cost us the most time.

1. Don't rely on Meta's transcript arriving. Meta accepted our transcription requests, but the transcripts often didn't come. Keep your own copy of the recording, and transcribe it yourself if Meta's hasn't arrived after a few minutes. If your customers mix Marathi, Hindi and English in one sentence, test your transcription model on real calls before trusting it.
2. Ring the person who already knows the customer. A customer who calls mid-conversation expects whoever they were chatting with. Route the call to the agent handling that chat first.
3. A call should behave like a message. It should move the chat to the top of the inbox, create a chat for a first-time caller, and show "Missed call" in the preview. Otherwise missed calls disappear.
4. Voicemail greetings must be mono Opus audio. Some .ogg files that aren't Opus played garbled and too fast. Convert every uploaded greeting before sending it to Meta.
5. Let AI read transcripts, but never reply to them. Feed the call transcript to your AI when it summarises a chat or suggests the next step. Don't let it trigger keyword replies or count as an unread customer message.

For the full technical detail, see Meta's Calling API documentation and calling pricing. For everything else that changed this year, see WhatsApp Business API pricing changes in 2026.

Frequently asked questions